800XL came with Ingot supply, tested to 5V ok, but used Raspberry Pi Zero 2.5 amp instead(has 5.33 and 5.19V under load output) Connect to LCD monitor/Tv and SIO2SD. Unit boots to lothareks menu, but has loud noise that should not be there and video not clean. Open up and find OS rom not fully seated. Board is fully socketed.Remove C56(was installed, not shown on schematic from Sams)bridge L5. Video much better and noise gone.Test mode shows 48 blocks Ram(FRE(0)=37873.connect keyboard.Have stuck key.Type 4 with Mylar.Take apart and reduce spring tension on bad key. Unit seems to work OK except the blue screen turns to green shade when idle for a while. Does not seem to affect game play. Unit missing 800XL badge on top cover.
600XL also came with Ingot supply(tested to 5V),not used. Could not get output to show on LCD monitor/Tv set to ch 2or3. Decided to install UAV and Din5 to get composite video. Now have video and sound. Maybe Tv did not pickup Rf from Atari? Install 64K upgrade with 4464-10 chips and 3 wire. Test mode shows 40 blocks, not 48, but FRE(0)=37902. Unit works fine with games.
What is causing blue to green change on the 800XL?
Thanks for looking.